Simon Pegg and Nick Frost (Hot Fuzz, Shaun of the Dead) reunite as sci-fi geeks taking a pilgrimage to America's UFO heartland. There they meet a smart-ass alien, Paul (voiced by Seth Rogen), who takes them on an insane road trip. As they struggle to return Paul home, the little green man might just take the outcasts from misfits to intergalactic heroes.